London has been battered by 50mph winds that have felled trees and caused travel chaos. Powerful gusts swept across the capital as the Met Office issued a yellow "be aware" weather alert for most of the country.

The new British Museum exhibition Life and Death in Pompeii and Herculaneum opens to the public on Thursday. Through more than 250 objects, many of which have never before left Italy, visitors will get a unique insight into the daily lives of ordinary Pompeiians whose city was preserved under volcanic ash.

First, some basic facts. The estimated population of Pompeii when Mount Vesuvius erupted was 15,000, and the year AD 79. Many of the bodies were preserved in the exact shapes they were in when they died.

Banquets were a big deal in ancient Rome and frescoes frequently show elaborate spreads being enjoyed by vivacious youngsters. Surprisingly, however, and more akin to modern life, cafés and fast-food outlets lined the streets. And on a day-to-day basis, the Pompeiian diet was healthy, consisting mostly of sea food and vegetables.

Wine in ancient Rome was more concentrated than it is today, but it was generally drunk watered down. Today, alcohol often leads to bedroom action, but for ancient Pompeiians too much wine would often lead to triclinium action – dining room sex. Brothels were commonplace as prostitution was legal and there was relatively little shame attached to the women involved. It was the chosen path for both upper- and lower-class women.

Pompeiians were frank in their presentation of sex, as evidenced by frescoes and carvings portraying graphic orgies and phalluses. One of the most famous erotic ancient Roman statues shows the god Pan – half-man, half-goat – having sex with a goat, which you get a chance to see for yourself in the exhibition.

Women in Pompeii had more power than elsewhere in the Roman Empire – they could be employed and could own land and houses. A fresco of baker Terentius Neo and his wife shows them as equal business partners, with her seemingly even in charge of the purse strings. This, too, is in the exhibition.

Relative gender equality also stretched to the realm of beauty and grooming. After examining their remains, Estelle Lazer, an archaeologist and physical anthropologist at the University of Sydney, claimed many women were hairy and overweight, a far cry from the "classical beauties’"in Pompeii frescoes.

And finally, only roughly half the population of Herculaneum was "ethnically Italian" – the rest were either slaves or former slaves from all over the world.

Life and Death in Pompeii and Herculaneum, British Museum, March 28-September 29. britishmuseum.org